Tribological and Antimicrobial Properties of Two-Component Self-Assembled Monolayers Deposited on Ti-Incorporated Carbon Coatings

Materials (Basel). 2024 Jan 14;17(2):422. doi: 10.3390/ma17020422.

Abstract

In this work, Ti-incorporated carbon coatings were used as substrates for modification with one- and two-component self-assembled monolayers of organosilane compounds using a polydimethylsiloxane (PDMS) stamp. This enabled the selective functionalization of surfaces with micrometric dimensions. The topography of the modified surfaces was defined using an atomic force microscope (AFM). The effectiveness of the modification was confirmed by measurements of the water contact angle and surface free energy using the Oss and Good method. Using a T-23 microtribometer with counterparts in the shape of balls that were made of steel, silicon nitride (Si3N4), and zirconium dioxide (ZrO2), the tribological properties of the obtained coatings were tested. These investigations showed that modification by using a PDMS stamp makes it possible to produce two-component ultrathin silane layers on Ti-containing carbon substrates. Two-component organosilane layers had higher hydrophobicity, a lower friction coefficient, and a smaller width of wear tracks than the one-component analogs. It was also found that the work of adhesion of the created surfaces had a significant influence on the value of the friction coefficient and the percentage value of the growth inhibition of bacteria.

Keywords: Ti-incorporated carbon coatings; antimicrobial activity; microtribology; self-assembled monolayers; silanes.